Question 1

What is the difference between probability and odds?

Accepted Answer

Probability is the ratio of favorable outcomes to total outcomes (e.g., 1/6 for rolling a specific number on a die). Odds compare favorable to unfavorable outcomes (e.g., 1:5 for rolling that number, meaning 1 way to succeed vs 5 ways to fail). To convert odds a:b to probability: P = a/(a+b).

Question 2

What is complement probability?

Accepted Answer

The complement of an event A is the event 'not A' (written A' or A-bar). P(A') = 1 - P(A). For example, if the probability of rain is 0.3, the probability of no rain is 1 - 0.3 = 0.7. The complement rule is useful when it is easier to calculate the probability of something NOT happening.

Question 3

Can probability be greater than 1?

Accepted Answer

No. Probability ranges from 0 to 1 (or 0% to 100%). A probability of 0 means the event is impossible, and 1 means it is certain. If your calculation gives a value outside this range, check your inputs -- favorable outcomes cannot exceed total outcomes.

Question 4

What does 'equally likely outcomes' mean?

Accepted Answer

This formula assumes all outcomes have the same chance of occurring (like a fair die or coin). If outcomes are not equally likely (e.g., a loaded die), you cannot simply divide favorable by total. You would need to know the individual probabilities of each outcome.

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